Lubricating compositions

ABSTRACT

Lubricating compositions which contain significant amounts of chlorinated oils (e.g. paraffin oils which have been chlorinated to more than 40 percent chlorine) are improved for use as metalworking lubricants by the inclusion therein of additive amounts (e.g. 5 weight percent) of one or more ethoxylated fatty amines (e.g. a tertiary amine having one C12-C18 fatty alkyl group or radical and 2 polyoxyethylene groups or radicals attached to the amine nitrogen atom). The improved lubricating compositions have a reduced tendency to corrode the metal being worked and are self-emulsifying, thereby permitting the improved lubricating compositions to be removed from the worked metal by aqueous or solvent methods (e.g. water washing).

ite States Patent Obermeier [151 3,657,129 1 Apr. 18, 1972 [54] LUBRICATING COMPOSITIONS [72] Inventor: Frank J. Obermeler, West St. Paul, Minn.

[73] Assignee: Economics Laboratory, Inc., St. Paul,

. Minn.

[51] Int. Cl. ..Cl0m1/20,Cl0m H32 [58] Field of Search ..252/5l.5 R, 392

[56] References Cited UNITED STATES PATENTS 2,529,188 11/1950 Rocchinietal ..252/58 2,917,160 12/1959 Turinsky OTHER PUBLICATIONS Ethoxylated Chemicals in Amour & Co. Booklet, 1955, pages 2, 3, l7, 18

Primary Examiner-Daniel E. Wyman Assistant Examiner-W. J. Shine Attorney-Merchant & Gould [57] ABSTRACT Lubricating compositions which contain significant amounts of chlorinated oils (e.g. paraffin oils which have been chlorinated to more than 40 percent chlorine) are improved for use as metal-working lubricants by the inclusion therein of additive amounts (e.g. 5 weight percent) of one or more ethoxylated fatty amines (e.g. a tertiary amine having one C C fatty alkyl group or radical and 2 polyoxyethylene groups or radicals attached to the amine nitrogen atom). The improved lubricating compositions have a reduced tendency to corrode the metal being worked and are self-emulsifying, thereby permitting the improved lubricating compositions to be removed from the worked metal by aqueous or solvent methods (e.g. water washing).

9 Claims, No Drawings BACKGROUND OF THE INVENTION Lubricating compositions are used in large volumes in many metal working operations. The role of a metal working lubricant is to form a protective film on the metal being worked to thereby reduce metal to metal contact, reduce friction, and dissipate heat so that the metal part can be worked (e.g. deep drawn) more easily without metal rupture, wrinkling, scratching, heat distortion, and the like. In addition, the lubricant serves to protect the metal working tools (e.g. the die and punch).

Liquid lubricating compositions (e.g. mineral oils) function by coating the metal being worked with a thin film of oil to thereby separate the metal part from the metal working tools. When the forces between the adjacent metal surfaces are great, (e. g. the forces between a metal part and a die) the success or failure of the lubricating composition is determined in part by the strength of the thin film of lubricant which separates the two metals.

In addition to performing well in the intended metal working operation (e.g. as by providing good drawability in deep drawing operations), a metal working lubricant should also be non-corrosive to the metal parts (i.e. to the workpiece) and should be economically cleaned or removed from the metal part after completion of the metal working operation.

Chlorinated oils have been used for many years as a major ingredient in liquid lubricating compositions intended for use in metal working operations, particularly because of their ef-' fectiveness under extreme pressure conditions. However, chlorinated oils, per se, are not generally removed with case from metal parts after working, and vapor degreasing is often required. In the past, this cleaning or removal problem has been reduced by the inclusion of emulsifiers in such lubricating compositions. The use of certain emulsifiers (e.g. nonyl phenoxy polyethoxy ethanol) permits chlorinated oils to be removed from metal parts after working by aqueous methods. However, even with the use of many emulsifiers, corrosion of the metal part being worked is still a problem. In fact, someemulsifiers are so hygroscopic that they materially increase the amount of rusting that occurs. It is generally believed that this rust or corrosion occurs on carbon steels and other metals because of the partial decomposition, due to heat and pressure of the chlorinated oil to thereby release chlorine which reacts with moisture to form hydrochloric acid which then starts the corrosion or rusting process. The corrosion can be observed as rust on ferrous metals and as stains on other metals (e.g. as stains on certain copper alloys). In general, this rust must be removed before the worked metal part can be completed or finished.

Accordingly, it has been a goal of both the lubricant manufacturers and the metal working industry to find a way to take advantage of the desirable metal working properties of chlorinated oils and at the same time reduce or eliminate the corrosion and cleaning problems ordinarily associated with the use of such chlorinated oils.

SUMMARY OF THE INVENTION I have discovered that liquid lubricating compositions which contain one or more chlorinated oils can be improved for use in metal working operations, particularly deep drawing operations involving carbon steels, by the addition thereto of additive amounts of ethoxylated fatty amines. These improved lubricating compositions are less corrosive to the metal parts being worked than the unimproved lubricating compositions and they can be removed from the metal parts by aqueous methods.

DETAILED DESCRIPTION OF THE INVENTION The improved lubricatingcompositions of this invention can be made by the simple mixing of a chlorinated oil with an ethoxylated fatty amine as hereinafter described. The resulting lubricating compositions may optionally include other lubricants (e.g. a mineral oil), diluents (e.g. petroleum solvents), and lubricant additives as known in the art (e.g. foam control agents, dyes, etc.).

THE ETHOXYLATED FATTY AMINES The ethoxylated fatty amines which can be used in the practice of the present invention include the following:

In the compounds represented by formulas I and II, R is a C -C fatty radical (e.g. C -C fatty radical). Suitable fatty radicals are those obtained from cocoanut fatty acids, soybean fatty acids, tallow fatty acids and the like. In formula II, R is a divalent hydrocarbyl radical, usually containing from two to six carbon atoms (e.g. a trimethylene radical). X, Y, and Z are numbers, the sum of'which is 2-15 in formula I and 3-15 in formula II. Desirably, the sum of X and Y in formula I will be 2-10, inclusive and the sum of X, Y and Z in formula II will be 3-10, inclusive.

Ethoxylated fatty amines of this type are commercially available (e.g. Ethomeens and Ethoduomeens, products of Armour and Company) and are known for their surface active properties. Such ethoxylated amines can be prepared by condensing the corresponding fatty amine or diamine (e.g. oleyl amine) with ethylene oxide. These ethoxylated fatty amines are cationic in nature, with those of formula II being more cationic in nature than those of formula I. The ethoxylated fatty amines of formula I are generally more oil soluble than those of formula II at the same ethylene oxide content.

As can be appreciated, fatty chain length, the saturation of this fatty chain, and the length and position of the polyoxyethylene chains can be varied. These variations make it possible to tailor make ethoxylated fatty amines for specific applications. With this in mind, the following generalities can be made.

Increasing the number of carbon atoms in the fatty radical tends to give a higher melting product and tends to increase the oil solubility and decrease the water solubility of the product. Increasing the degree of unsaturation in the fatty radical, at the same carbon content of the fatty chain, tends to reduce the melting point of the product. Increasing the amount of ethylene oxide in the product (i.e. lengthening the polyoxyethylene chains) tends to increase the water solubility and decrease the oil solubility of the product.

Oil solubility of the ethoxylated fatty amines is important. With amines of Formula I, we have found that 10 mole adducts (i.e. x+y=l0) are on the edge of good oil solubility. However, through the use of proper diluents (e.g. mineral spirits) and/or by using the higher adducts (e.g. 15 mole adducts) in combination or admixture with the more oil soluble adducts (e.g. 2 mole adducts) an acceptable level of oil solubility can be achieved. However, I have not yet been able to obtain satisfactory solubility at ethylene oxide contents substantially above 15 moles (e.g. at 50 moles of ethylene oxide) per mole of amine.

The ethoxylated fatty amines will be used in lubricating compositions in minor but effective amounts. In general, the amount of ethoxylated fatty amine (or a mixture of such amines) will ordinarily be an additive amount of up to 15 weight percent, based on the total or final weight of the improved lubricating composition. More usually, such ethoxylated fatty amines will be used in amounts of from 1 to 12 weight percent (e.g. 3 to 9 weight percent) on the same basis.

THE CHLORINATED OILS The present invention is applicable to any of the chlorinated oils commonly used in metal drawing operations. However, all chlorinated oils do not work with equal effectiveness. The best metal working properties seem to be associated with chlorinated oils with high chlorine contents (e.g. chlorine contents above 30 percent, above 40 percent, above 50 percent or even above 60 percent).

Chlorinated oils are prepared by chlorinating paraffinic hydrocarbons including both the light oils (e.g. C paraffrnic oils) and the paraffin waxes. Such chlorinated oils are often light yellow to amber colored liquids. A typical average formula is C H CI The lubricating compositions of the present invention may contain as little as percent chlorinated oil (or some mixture thereof), based on the total weight of such lubricating composition. However, it is more common for such lubricating compositions to contain at least percent chlorinated oil, desirably at least 40 percent chlorinated oil, and preferably at least 50 percent chlorinated oil. If desired, a chlorinated oil or a mixture of chlorinated oils can represent more than 60 percent or 80 percent of the lubricating composition. In fact, the lubricating compositions of this invention can consist of only the chlorinated oil (e.g. 99 percent Oil) and the ethoxylated fatty amines of this invention (e.g. 1 percent ethoxylated fatty amine).

OTHER INGREDIENTS AND GENERAL INFORMATION Except for such additives as may be present (e.g. the ethoxylated fatty amines), the balance of these lubricating compositions can be one or more other lubricants (e.g. mineral seal oil) or diluents (e.g. a petroleum solvent).

In addition to the reduced tendency of the lubricating compositions of this invention to cause corrosion of the metal parts being worked, another advantage of these lubricating compositions is the fact that they can be removed from worked metal parts by aqueous methods (i.e. by washing with water, optionally assisted by the use of detergents or other cleaning aids such as alkaline cleaners). Of course, solvent cleaning methods can also be used (e.g. trichloroethylene), but such expensive cleaning methods are not required.

EXAMPLES l-S Examples l-8, set forth in Table l which follows, illustrate the preparation of improved lubricating compositions according to this invention. Included are examples showing the simple practice of this invention (Example 1), the use of diluents and other lubricants (Examples 2 and 5-7), the use of mixtures of ethoxylated fatty amines (Examples 3-8), and the use of a mixture of two chlorinated oils of different chlorine contents (Example 8).

The chlorinated oils used in these examples are chlorinated paraffin oils (commercially available from Pearsall Corp.).

The ethoxylated fatty amines hereinafter identified by the letters A, B, C and D were prepared by condensing ethylene oxide with the appropriate amine using the indicated number of moles of ethylene oxide per mole of amine.

The ethoxylated fatty amine identified as A is a tertiary amine having one fatty radical (derived from cocoanut TABLE I.-IMPROVED LUBRICAIING COMPOSITIONS Example number Ingredient 1 2 3 4 5 6 7 R Example number Ingredient l .3 3 l 5 Ii 7 6. Ethoxylated fatty fatty acid) and two polyoxyethylene radicals, all three radicals being attached to the nitrogen atom. This product is prepared by condensing 2 moles of ethylene oxide per mole of cocoa amine.

The ethoxylated fatty amine identified as B in Table I is a tertiary amine having one fatty radical (derived from tallow fatty acids) and two polyoxyethylene radicals, all three radicals being attached to the nitrogen atom. This product is prepared by condensing 5 moles of ethylene oxide per mole of tallow amine.

The ethoxylated fatty amine identified as C in Table I is a tertiary amine having one fatty radical (derived from soya fatty acids) and two polyoxyethylene radicals, all three radicals being attached to the nitrogen atom. This product is prepared by condensing 10 moles of ethylene oxide per mole of soya amine.

The ethoxylated fatty amine identified as D in Table I is a diamine obtained by reacting N-tallow trimethylene diamine with 10 moles of ethylene oxide per mole of said diamine.

EXAMPLES 9-24 To illustrate the advantages of the present invention, the corrosion inhibiting effect of various ethoxylated amines was tested under controlled laboratory conditions. The test procedure was as follows. Each of the lubricating compositions to be tested was applied to the top of a steel coupon or test panel. A second coupon or test panel was then placed on top, and the two test panels were clamped tightly together. The resulting sandwich was then placed in an oven at C. for 15 minutes. The sandwich was then removed and opened, while hot, to the atmosphere. The test panels were then immediately placed in a humidity chamber controlled to 98 percent relative humidity and 70 F. Visual observations of the test panels were made after exposure to the high humidity for O, 2, 24, and 96 hours. The results which were obtained are shown in Table II which follows.

Each of the lubricating compositions shown in Table II was a simple mixture of a chlorinated paraffin oil containing approximately 40 percent chlorine (Chemtron CPF-DX, a product of Pearsall Corp.) and the indicated amount of additive. For purposes of comparison, two control compositions were prepared. 7

The first (control 1) was merely the chlorinated oil without any additives. The second (control 2) was the chlorinated oil with a known emulsifier added thereto (i.e. lgepal CO-53 which is nonyl phenoxy polyethoxy ethanol). After 24 hours under the test conditions, the test panels which had been coated with control 1 lubricating composition were completely covered with a light layer of rust. Moreover, control l" lubricating composition was difficult to remove from the metal panels and could not be effectively removed by ordinary aqueous methods. After only 2 hours under the test conditions, the test panels which had been coated with control 2 lubricating composition were completely covered with a heavy layer of rust.

In sharp contrast, none of the lubricating compositions which contained an ethoxylated fatty amine permitted such rusting, even after exposure to the high humidity for 96 hours. Furthermore, the lubricating compositions of this invention could be removed from the metal test panels by ordinary aqueous methods.

CHLORINATED OIL Additive of type Visual observations M Additwe I, II, weight, 24 96 Example R R X+Y X+Y+Z percent hours hours hours hours 0 OK OK Covered with Covered with light rust. light rust.

7. Heavy rust Heavy rust. 1.0 OK OK Trace only- Trace only.

15.0 OK OK OK Do. 7. 5 OK 0 K Do. 7. 5 OK OK Do.

3. 75 OK 0 K Do.

3. 75 OK 0 K Do.

3. 75 OK OK D0.

3. 75 OK OK Do.

3.75 OK OK Do.

3. 75 OK OK Do.

3. 75 OK OK Do.

3.75 OK OK "do" Do.

7. 5 OK OK Slight trace Slight trace. 7. 5 0K OK OK Trace only.

3.75 OK OK OK Do.

3. 75 OK OK D0.

1 Light stain. 2 Heavy rust.

3 Trimethylcne. A

EXAMPLE 25 This example illustrates the use of the improved lubricating compositions of the present invention in a deep drawing process.

In this example, gas cylinders were deep drawn through three progressive die stamping operations. The lubricating composition of this example was a mixture of 95 percent of a chlorinated oil having approximately a 50 percent chlorine content (FLX-00l2, a product of Pearsall Corp.) and 5 percent of an ethoxylated amine which was a 50:50 mixture of two ethoxylated fatty (tallow) amines of Formula I as previously given. One of the amines contained 2 moles of ethylene oxide and the other contained 5 moles of ethylene oxide.

Using this lubricating composition, cylinders could be deep drawn and then stored for as long as three weeks in conditions of high summer heat and humidity without producing any visually observable rust. At the end of that time (i.e. about three weeks), the lubricating composition was readily removed from the cylinders by aqueous methods.

By comparison, when the procedure was repeated using as the lubricant, a lubricating composition consisting essentially of 95 percent of an equivalent chlorinated parafi'm oil containing approximately 50 percent chlorine, and 5 percent of a commercially available surfactant [Nonyl phenoxy poly (ethoxy) ethanol], the deep drawn cylinders began to rust within l-2 days after drawing. As a result, the cylinders required extensive cleaning (e.g. as by wire brushing) to remove the rust after the cylinders had been stored for three weeks.

What is claimed is:

1. In the process of working metals wherein the metal to be worked is contacted with a lubricating composition, the improvement which comprises using as said composition a liquid lubricating composition consisting essentially of:

a. at least weight percent of a chlorinated oil or mixture thereof having a chlorine content above 30 percent;

b. an additive amount of up to 15 weight percent of ethoxylated fatty amine selected from those having the formulas:

Wherein R is a C -C fatty radical, wherein R is a divalent C C hydrocarbyl radical, and wherein x, y and z of both formulas are numbers the sum of which is 2-15 in formula I and 3-15 in formula II; and

c. the balance to percent being selected from the group consisting of'lubricants, diluents, and lubricant additives.

2.lmproved processes of claim 1 wherein the metal working process is a deep drawing process.

3. Improved processes of claim 1 wherein the lubricating composition comprises:

a. at least 50 weight percent of a chlorinated oil or mixture thereof having a chlorine content of at least about 40 percent; and

b. 3-9 weight percent of ethoxylated amine of formula I or a mixture thereof, the sum of x and y being 2-10.

4. Improved processes of claim 3 wherein said lubricant consists essentially of:

a. about 92.5 weight percent of chlorinated oil;

b. about 7.5 weight percent of a mixture of:

l. ethoxylated cocoa amine prepared by condensing 2 moles of ethylene oxide per mole of cocoa amine; and 2. ethoxylated tallow amine prepared by condensing 5 moles of ethylene oxide per mole of tallow amine.

5. Improved processes of claim 3 wherein said lubricant consists essentially of:

a. about 65 weight percent of chlorinated oil;

b. about 15 weight percent mineral oil;

c. about 15 weight percent mineral spirits; and

d. about 5 percent of a mixture of:

l. ethoxylated cocoa amine prepared by condensing 2 moles of ethylene oxide per mole of cocoa amine; and 2. ethoxylated tallow amine prepared by condensing 5 moles of ethylene oxide per mole of tallow amine.

6. Liquid lubricating compositions having a reduced tendency to corrode metal when used in metal working operations, said compositions consisting essentially of:

a. at least 15 weight percent of a chlorinated oil or mixture thereof having a chlorine content above 30 percent;

b. an additive amount of up to 15 weight percent of ethoxylated fatty amine selected from those having the formulas:

Wherein R is a C -C fatty radical, wherein R is a divalent C -C hydrocarbyl radical, and wherein x, y and z of both formulas are numbers the sum of which is 2-15 in formula 1 and 3-15 in formula ii; and

c. the balance to 100 percent being selected from the group consisting of mineral oil, mineral spirits, and corrosion in- 2. ethoxylated tallow ainine prepared by condensing hibitors. moles of ethylene oxide per mole of tallow amine. 7. The lubricating compositions of claim 6 which comprise: 9. Lubricating compositions of claim 7 which consist essena. at least 50 weight percent of a chlorinated oil or mixture tially of;

thereof having a chlorine content of at least about 40 pc 5 a. about 65 weight percent of chlorinated oil;

Cent; and b. about 15 weight percent mineral oil; b. 3-9 weight percent of ethoxylated amine of formula I or a c. about 15 weight percent mineral Spirits; and

mixture thereof, the sum of x and y being 2-10. 8. Lubricating compositions of claim 7 which consist essentially of: 10

a. about 92.5 weight percent of chlorinated oil;

d. about 5 percent of a mixture of:

l. ethoxylated cocoa amine prepared by condensing 2 moles of ethylene oxide per mole of cocoa amine; and

b about-7.5 weight percent ofa mixture of: 2. ethoxylated tallow amine prepared by condensing 5 l. ethoxylated cocoa amine prepared by condensing 2 moles ethylene oxide Per mole ofmnow aminemoles of ethylene oxide per mole of cocoa amine; and 

2. Improved processes of claim 1 wherein the metal working process is a deep drawing process.
 2. ethoxylated tallow amine prepared by condensing 5 moles of ethylene oxide per mole of tallow amine.
 2. ethoxylated tallow amine prepared by condensing 5 moles of ethylene oxide per mole of tallow amine.
 2. ethoxylated tallow amine prepared by condensing 5 moles of ethylene oxide per mole of tallow amine.
 2. ethoxylated tallow amine prepared by condensing 5 moles of ethylene oxide per mole of tallow amine.
 3. Improved processes of claim 1 wherein the lubricating composition comprises: a. at least 50 weight percent of a chlorinated oil or mixture thereof having a chlorine content of at least about 40 percent; and b. 3-9 weight percent of ethoxylated amine of formula I or a mixture thereof, the sum of x and y being 2-10.
 4. Improved processes of claim 3 wherein said lubricant consists essentially of: a. about 92.5 weight percent of chlorinated oil; b. about 7.5 weight percent of a mixture of:
 5. Improved processes of claim 3 wherein said lubricant consists essentially of: a. about 65 weight percent of chlorinated oil; b. about 15 weight percent mineral oil; c. about 15 weight percent mineral spirits; and d. about 5 percent of a mixture of:
 6. Liquid lubricating compositions having a reduced tendency to corrode metal when used in metal working opErations, said compositions consisting essentially of: a. at least 15 weight percent of a chlorinated oil or mixture thereof having a chlorine content above 30 percent; b. an additive amount of up to 15 weight percent of ethoxylated fatty amine selected from those having the formulas:
 7. The lubricating compositions of claim 6 which comprise: a. at least 50 weight percent of a chlorinated oil or mixture thereof having a chlorine content of at least about 40 percent; and b. 3-9 weight percent of ethoxylated amine of formula I or a mixture thereof, the sum of x and y being 2-10.
 8. Lubricating compositions of claim 7 which consist essentially of: a. about 92.5 weight percent of chlorinated oil; b. about 7.5 weight percent of a mixture of:
 9. Lubricating compositions of claim 7 which consist essentially of: a. about 65 weight percent of chlorinated oil; b. about 15 weight percent mineral oil; c. about 15 weight percent mineral spirits; and d. about 5 percent of a mixture of: 